This invention relates to the use of anionic polymers to reduce the viscosity of a magnesium hydroxide filter cake paste.
Magnesium hydroxide is obtained from seawater by precipitation with the addition of dolomite. Its principal use is as a highly pure powder for use in toothpaste, anti-acid formulations and as a coating to silicon steel. Less pure grades of magnesium hydroxide have been used in slurry form as a fuel oil additive.
It is necessary to reduce the viscosity of magnesium hydroxide filter cake pastes in order to make it pumpable. The viscosity has previously been reduced by the addition of water. The addition of water reduces the active concentration. The magnesium hydroxide will not remain suspended and, once settled, more difficult to move through a delivery pipe.
It is an object of the instant invention to produce a stable dispersion or suspension, reduce the viscosity and maintain the active concentration.
It is known to use neutralized polyacrylic acid to reduce the viscosity of magnesium oxide aqueous slurries (U.S. Pat. No. 4,230,610). However, magnesium oxide is obtained from the ore, magnesite. This is a completely different art. The methods of recovery are unrelated.